By default, MySQL databases on our shared hosting are only accessible from within the server itself. If you need to connect to your database from an external service (for example a Minecraft server, a VPS, or any application hosted elsewhere), you must first whitelist the remote IP address.
Follow the steps below to grant remote access:
Step 1 – Obtain the IP address of the remote service
Step 2 – Whitelist the IP in Plesk

After the IP has been added, your external service should be able to connect to the database using the normal MySQL hostname, username, password, and database name.
If you continue to have connection issues after whitelisting the IP, please open a support ticket and include the remote IP you are trying to connect from.